California lawmakers have approved a plan to borrow $6 billion from a state savings account to pay down massive debt in the state's largest public-employee retirement program.

The Senate approved the measure 24-13 on Monday, sending it to Gov. Jerry Brown despite concerns from some lawmakers about its risks.

Brown says the state can borrow from its own short-term investment account and earn a higher return through the more aggressive investments at the California Public Employees' Retirement System. He says the proposal would save $11 billion over time through lower annual pension costs.

Democratic Sen. Steve Glazer of Orinda says the idea may have merit but lawmakers should wait until it's been more thoroughly studied.

CalPERS has money to cover only about two-thirds of the benefits promised to retired public employees.